Like Slow Horses but darker: Betrayal is the “exceptionally-written” ITV spy thriller to rival the very best

Move over Gary Oldman, there’s a new spy in town in the form of Shaun Evans. The Endeavour star is leading the cast of ITV’s "exceptionally-written" spy thriller, Betrayal, and it’s set to rival the very best. Think of it like Slow Horses but darker.

The upcoming series will introduce us to John Hughes (Evans), a spy trying to avert a serious and "dark" threat to national security – while dealing with his own personal demons. Described by ITV as "an emotionally intelligent, thrilling and darkly funny thriller" – it’s got "new favourite TV show" written all over it.

Ahead of Betrayal’s arrival on our screens, here’s everything you need to know about the series, including the cast, plot and release date.

What is ITV's Betrayal about?

Set in London and Manchester and written by award-winning playwright and screenwriter David Eldridge, the new series enters us into the clandestine world of MI5. John Hughes (Shaun Evans) joined the Security Service during the war on terror and was at the forefront of averting the biggest terrorist plots on UK soil. Now, he’s in his mid-40s, married with two children and struggling to adjust to the “new” MI5.

On a hunch, John meets Ehsan, a British Iranian man with links to the Manchester gangland who claims he has intelligence about a plot on UK soil. Before he has a chance to share intel however, Ehsan is executed by a lone gunman - and John impulsively kills the assassin in retaliation. Not only has John killed a man, he now finds himself in direct collision with his superiors, who are furious he’s managed to get himself involved in a Manchester gang turf war.

John, however, believes there’s more to the story and it’s simply not possible to leave things alone. He starts digging into Ehsan’s past, knowing he’ll have to redeem himself if he’s to save his career and his reputation. At the same time, he’s struggling with his own mental health having killed another human.

According to the official synopsis, "John’s efforts to save his career and his marriage are also tested by Mehreen, an intelligence operative who is brought in to take over John’s duties on the Iran desk. Their connection is electric, and John must wrestle with temptations his younger self would readily have surrendered to.

"Struggling with his own demons, his love for his family and his complicated loyalty to the institution he’s been part of for over 20 years, John sets out to find the truth of the explosive security threat to the UK before it’s too late."

Shaun Evans says of the series: "I’m delighted to be returning to ITV with this exceptionally well written and timely project. It’s a great privilege to reunite with David Eldridge and bring to life his insightful take on the world of espionage. And it is of course a joy to be collaborating once again with the first-rate team at Mammoth Screen. I look forward to sharing it with ITV audiences soon."

Writer David Eldridge has called the series "an espionage drama rooted as much in the trials and betrayals of family life as in the bloody, dangerous business of spying”, while ITV Drama Commissioner Huw Kennair-Jones has described John Hughes as “a fascinating character.”

He says: "John Hughes is a complex man trying to navigate his way through the evolving world of espionage as he also tries to save his marriage. We’re thrilled that Shaun Evans will be bringing John to life as he reunites with the brilliant team at Mammoth to make what is sure to be an exciting and compelling drama."

Who's starring in Betrayal?

As it stands, Shaun Evans is the only confirmed cast member. As soon as we have further updates, we’ll share them here.

What has Shaun Evans starred in before?

You may recognise Shaun Evans from his role as a young Endeavour Morse in the ITV drama series Endeavour. He’s also played Coxswain Elliot Glover in BBC One’s Vigil and real-life murderer John Sweeney in ITV's Until I Kill You.

How can I watch Betrayal?

ITV hasn't yet shared an official release date for Betrayal, but we do know that it's expected to arrive on our screens later this year. In the meantime, you can see our pick of the best spy thrillers to watch now here.